Manufacture of cellulosic products



June 7, 1966 GREINER ET AL 3,254,374

MANUFACTURE OF CELLULOSIC PRODUCTS Filed April 18. 1960 7 Sheets-Sheet 1June 7, 1966 c. J. GREINER ET A. 3,254,374

MANUFACTURE OF CELLULOSIC PRODUCTS '7 Sheets-Sheet 2 Filed April 18.1960 June 7, 1966 C,J, GRElNER ET AL 3,254,374

MANUFACTURE OF CELLULOSIC PRODUCTS Filed April 18. 1960 7 Sheets-SheetL5 June 7, 1966 c-.J.eRI-:lNER E AL ,2 4,

IANUFACTURE 0F CELLULOSIC PRODUCTS I Filed April 18. 1960 7 Sheets-Sheet4 June 7, 1966 c. J. GREINER ET AL MANUFACTURE OF CELLULOSIG PRODUCTS 7Sheets-Sheet 5 Filed April 18. 1960 .wmv QM w June 7, 1966 c. J. GREINERET AL 3,254,374

MANUFACTURE OF CELLULOSIC PRODUCTS '7 Sheets-Sheet 6 Filed April 18.1960 June 7, 1965 c. J. GREINER ET AL 3,254,374

MANUFACTURE OF CELLULOSIC PRODUCTS 7 Sheets-Sheet 7 Filed April 18. 1960United States Patent MANUFACTURE OF CELLULOSIC PRODUCTS Charles J.Greiner, Menasha, and Henry R. Cloots and Harold V. Rutkus, Neenah,Wis., assignors to Kimberly-Clark Corporation, Neenah, Wis., acorporation of Delaware Filed Apr. 18, 1960, Ser. No. 22 ,875

13 Claims. (Cl. 19145) This invention relates generally to an improvedmethod of fabricating absorbent bandages; to improvements in apparatusfor the high speed production thereof; and to improvements in theresulting product. The invention is particularly applicable tothe'pleating of the tab portions of a sanitary napkin wrapper extendingbeyond opposite ends of the enclosed absorbent pad for attachment tobelts or undergarments during use.

A major object of the invention is to provide an improved method ofpleating sanitary napkin tab ends during the fabrication thereof on highspeed production apparatus. 7

An equally important object is to provide an improved method offabricating sanitary napkins with outwardly tapering and marginallypleated tab end portions symmetrically reduced to narrow the width ofthe tab ends in respect to the pad width in a manner to increase pinstrength while facilitating attachment to belts and the like.

An additional object is to provide improvements in apparatusincorporating the concepts herein taught for the high speed productionof sanitary napkins having neatly tailored tapered tab ends marginallyoverpleated in a symmetrical manner to facilitate threading throughsupporting belts.

Still another object is to provide improved apparatus for the high speedproduction of wrapper enclosed absorbent bandages, such as sanitarynapkins having tapered tab ends formed of certain materials desirablefor such end use but which exhibit certain undesirable machinecharacteristics during processing on equipment designed for the highspeed inpleating of tab ends. The present invention thus permits the useof a much wider range of wrapper materials than does the conventionalinpleating method.

A further object is to provide an improved sanitary the same referencenumeral,

FIG. 1 illustrates in perspective a portion of a sanitary napkin a tabend of which incorporates the invention,

FIG. 2 illustrates in perspective a sanitary napkin having both tab endspleated in accordance with the invention,

FIG. 3 is an end view showing the doubly pleated tab end of FIG. 2greatly enlarged,

FIG. 4 illustrates in perspective one stage of the method of theinvention, I

FIG. 5 is similar to FIG. 4 but shows an advanced stage of Web pleating,

FIG. 5a illustrates in perspective the feeding and delivery arrangement,

FIG. 6 shows in plan the constructional details of the web forming andpleating apparatus as partially shown in FIGS. 4 and 5,

FIG. 7 shows in side elevation the apparatus of FIG. 6,

FIG. 8 is an enlarged fragmentary elevation taken along wrapper betweensuccessive pads during passage through a constricting nip but prior tobeing shaped by pleat forming tuckers,

FIG. 14 shows the change in wrapper configuration at the upstream end ofthe tuckers,

FIG. 15 illustrates the wrapper configuration at the downstream end ofthe tuckers, and 1 FIG. 16 is a plan view of the pleating ramp shown inperspective in FIG. 11.

While it is known to taper outwardly as well as to marginally pleatsanitary napkin wrapper tab ends, substantial problems are involved inthe operation of high speed apparatus designed to introduce both thedesired degree of taper and to effect consistently uniform known types'of marginal pleats. Simple over-pleating such as a diagonal fold-overof the tab end portions from a position adjacent the absorbent pad alongan oblique line of taper outwardly of the pad does not utilize the fullpotential of available pin strength. Serious production difiiculties arepresented in obtaining such folded over pleats in the tubular tensionedwrapper material between similarly spaced pads without slitting thematerial, a step which has proved impractical at high mass productionspeeds. Marginal infolds of moderate depth symmetricallyformed betweenthe outer plies of tab ends and accompanied by some transverse taperingof the tab ends are rather Widely employed, although manufacturingdifliculties encountered at high production speeds such as maintainingproper alignment and configuration of the wrapper material commonlyresult in non-uniformity of folds, hence either a high rejection rate ora lowering of tolerance standards. The method and apparatus hereindescribed permits the high speed production of improved fibers.Manufacturers seek constantly to improvet-heir wrapper materials inrespect to appearance and softness, tensile strength, fluid permeabilityand pin strength, while maintaining manufacturing costs at acceptablecompetitive levels. Since improved wrapper materials often vary as tophysical, hence processing, characteristics it is of major importancethat production equipment be capable of satisfactorily processing a widerange of wrapper materials without requiring modification or re-designthereof. The present invention permits satisfactory process-.

ing of a wide range of such material by avoiding the necessity ofsubjecting the material to high stresses during pleat formation. Therequired web displacement, meaning the extent to which any discrete areaof the wrapper must be moved during formation of pleated tab ends isconfiguration.

a substantially lowered, as compared to inpleating, by the method andapparatus herein taught. The term web is used alternately herein withwrapper and wrapper materia to mean any of the above mentioned materialsor modifications thereof.

Satisfactory inpleating such as by the apparatus taught in co-pendingPukis and Rutkus US. application 725,108, filed March 31, 1958, nowPatent No. 3,020,599, and assigned to applicants assignee requiresaccurate alignment of the web in the machine and rather exactingcontinuous maintenance of all machine adjustments. Improperly pleatedtab ends, such as those with the web margin extending laterally of apleated margin frequently result from improper machine maintenance. Theweb must be sufiiciently stressed to maintain a transverse configurationbetween pads roughly that of the corresponding pad Also, the inpleatingblades have a tendency to pass either over or under a lightly stressedweb instead of forming a pleat. Such initially required wrapper tensionis substantially increased as the blades employed in inpleating forcethe side-(wall wrapper material inwardly between the tab forming outerplies to an extent much greater, as above mentioned, than is required bythe overpleating method of the present invention. Inpleated portions ofthe wrapper material, thus necessarily placed under high stresses duringformation, are therefore substantially biased toward lateral expansionas they leave the folding blades and prior to passage through closelypositioned ironing rolls which fix the pleats.

While it is conventional practice to iron infolded pleats after forming,structural limitations dictate the necessity of spacing the ironingrolls at least a short distance from the pleating blades. The type ofpleating herein taught is easily effected without the necessity ofsubjecting the wrapper material to the above mentioned stresses, hencethere is no appreciable change in web configuration between the finalforming steps and ironing. For the above reasons, many materials whichdo not take an acceptable inplcat either because they do not keep inproper machine alignment or because they will not hold their pleatsprior to ironing are easily over-pleated in accordance with thisinvention.

FIGS. 1 and 2 illustrate a sanitary napkin comprising a pad portion 48enclosed in a fluid pervious wrapper 12 having portions extending beyondthe opposite ends of pad 48 to form tab ends 14 and 16 which may be ofequal or unequal length. Tab end 14 is shown marginally over-pleated at18 and 20 in accordance with the invention. As shown in the enlarged endview of FIG. 3, a portion of the wrapper material is marginally foldedover the upper overlapping ply 34 of tab end 14 with a like portionfolded over the lower ply of the central portion of 14. The marginalfolds 18 and 20 preferably start at a position slightly outwardly of theends of pad 48 and increase in depth along convergent fold linesextending toward the end of each tab portion until the desired tab endwidth is obtained. The fold lines may be linear or slightly arcuate toprovide the neatly tapered tab end configuration illustrated. Such ataper may extend continuously to the end of the tab end or may lead toportions of uniform width as shown.

As shown in the enlarged end view of FIG. 3, the present method convertsthe generally rectangular configuration which the wrapper definestransversely of each pad into tab end configurations defining doublepleats {l8 and '20 formed by overfolding rather than infolding marginalportions of the wrapper material. The production difficulties mentionedas inherent in the accordion-type infolding method are thus avoided.Both the inner and outer plies of the double pleats '18 and 20 are ofinwardly open and outwardly closed U-config-uration as distinguishedfrom the inwardly closed and outwardly open pleats of V-configurationobtained by the inpleating method. Double marginal pleat 18 comprises amarginally closed outer ply portion forming the exposed portions of theupper and lower double pleats, the inner margins of which are reversedat 22 and 24 to form within the area of the exposed pleat portions twoadditionally outwardly closed -U-configurations as the outwardlyextending inner ply portions 26 are reversed to form the closed end ofthe inwardly defined Us, the inner leg portions 28 of which are integralextensions of the bottom ply 30 and the overlapped upper tab end ply-34,respectively. While the marginal pleats shown in FIG. 3 are formed in amanner to position one side margin 36 of the wrapper material inwardlyof double pleat 18 and to position the other side margin 38 thereofinwardly of the opposite double ply 20, the formation of somewhat widerover-folded marginal pleats, as below described, may result in thepositioning of wrapper margins 36 and 38, respectively, well inside thedouble pleats 18 and 20, but still positioned between the lower tabpleat 30 and the upper overlapped tab pleat 34. In some instances,however, with very wide and substantially abutting marginal pleats thusformed, the wrapper margins 36 and 38 may extend completely through thedouble pleats 18 and 20 and partially around either of the two innermostportions of U-configuration to terminate, for example, between one ofthe pleat portions 26 and the outermost pleat portion contiguousthereto. The constructional advantages of the improved tab ends arelater explained.

The apparatus illustrated in perspective in FIGS. 4 and 5, the detailedconstruction of which is shown in other figures, comprises a frameworkshown at 40, FIG. 8, along which a tunnel-like wrapper guide 42 ofinverted U-configuration extends in a linear path. A beltlike conveyor44 immediately below guide 42 and forming a bottom closure for the guidecontinuously moves an elongate wrapper-forming web 46 which is fed froma supply roll 47, shown in FIG. 5a, onto belt conveyor 44. Absorbentpads 48 are sequentially fed in evenly spaced relation down chute 35onto conveyor carried web 46 from a suitable supply source, the web 46moving at a uniform speed toward the left as shown as folding ramps 50and 52, associated with guide 42, progressively overfold the web aboutpads 48 into a tubular configuration overlapped along the tops of thepads, the margins of the overlapped web portion being shown at 38.

FIGURE 5a also illustrates in perspective the feeding and deliveringarrangement. As shown in the drawing, wrapper forming web 46 iscontinuously fed from supply roll 47 onto moving conveyor belt 44.Conveyor belt 44 is driven by roll 45 and passes over guide rolls 37 and39. The latter r-olls urge belt 44 in sliding engagement with theunderside of horizontal frame member 40 to provide, in combination withtop guide member 42, a forming chamber for moving web 46. Absorbent padelements 48 are fed from chute 35 onto belt-supported web 46 atregularly spaced intervals, as web 46 moves from right to left. Web 46,carrying spaced pads 48, then passes through vertical frame member 41,which has mounted on the front portion thereof a presser foot 43. As thepads 48 pass under foot 43, they are firmly pressed into non-slidingengagement with web 46 and move along with web 46 as the side edges ofthe web are progressively folded over the pads 48 by folding ramps 50and 52, as previously described, to form a tubular configuration ofsubstantially the transverse perimeter of the enclosed pads. The web 46,enfolding spaced pads 48 in said tubular configuration, is thenmarginally pleated in the area between pads by operation of elementsshown generally at 63 and 68. As subsequently described in more detail,element 63 vertically depresses the central portions of the tube toprovided an I-beam configuration, while element 68 moves inwardly in ahorizontal plane to fold inwardly the crossbars of the I-beam configuration. The marginally formed pleats are pressed flat by heated ironerrolls 71 and 73. The web-enwrapped pad, and the pressed and pleatedwrapper then continue on through driven rolls 51 and 53 which serve tomaintain forward tension on the assembly as it moves through theoperation. As shown in the drawing, rolls 51 and 53 have mated surfaces,with reduced-radii portions 55 and 57 having a circumferential arc of alength corresponding .to the length of the napkin body portions 48, andthe raised surface portions 59 and 61 having a circumferential arc of alength corresponding to the length of the pressed wrapper in the spacebetween successive napkin bodies. Rollers 51 and 53 operate at a nippressure sufiicient to maintain the web under tension to retain thetubular configuration previously described. The pleated wrapper issubsequently severed transversely to provide individual sanitary napkinunits.

The illustrated method of continuously enclosing spaced absoribent padsin a wrapper material is known, the prese'nt invention being directed..to the formation of the portions of the wrapper material betweensuccessive pads into improved marginally pleated tab ends. Web foldingis completed before conveyor belt 44 leaves its linear path duringpassage about its forward drive pulley 54, at which position theelongate assembly of web enclosed pads is fed onto an adjacent elevatingramp 56 having an obliquely depressed receiving end 58 marginally of ahorizontal portion 60 leading into a narrowed inclined portion 62 'whichin turn leads upwardly to an elevated shelf-like portion 64. Ramp 56serves the function of momentarily supporting the lower mid-portion ofthe pad enclosing web while elevating that portion in respect to outerunsupported portions thereof as the mid-portion passes through a contourchanging constriction nip 66 formed between the inclined ramp portion 62and a constricting shoe 63 intermittently positioned in spaced relationto and above the ramp, transversely to reshape the tubular web from thesubstantially rectangular pad defined shape as shown in FIG. 12 into thesubstantially I-beam configuration shown in FIG. 13.

The improved method of marginally forming the symmetrically pairedoverpleats of the invention is clearly illustrated in FIGS. 4, 5, and5a. Since pads 48 and the web guide 42 are both transverselyrectangular, those web portions between the pads assume a likeconfiguration, it being understood that the web is subjectedcontinuously to suflicient forward tension, by pressing roll 71 and 73and by drawing rolls 51 and 53, to hold that configuration untilre-shaping as below described. As a wrapper enclosed pad 48 is drawnfrom conveyor 44 and over ramp 56 the web bridges that pad and atrailing pad while being maintained under suflicient tensioncontinuously to stress the web into tubular configuration. With a pad 48in the position shown inFIG. 5, the web constricting shoe 63 is in .aretracted position above the path of web travel, and a pair of marginaltuckers 68 are also in positions of retraction laterally-f the web path.As later described, shoe 63 and tuckers 68 move into the path of webtravel in synchronously timed relation to the rate of pad movementthrough the respective path of movement of intermittently operablemembers 63 and 68. As the trailing end of pad 48 clears the curved lowerend 70 of shoe 63, the shoe is rapidly cammed down to position the end70 thereof in nipforming spaced relation to a narrowed portion 62 oframp 56, a plan view of ramp 56 being shown in FIG.

16. The nip-forming portions of the shoe and ramp are of substantiallyequal width. The resulting elongate nip 66 vertically narrows downamid-portion of the web perimeter to change the shape thereof from thegenerally rectangular transverse configuration shown in FIG. 12 to thesomewhat I-beam configuration of FIG. 13. Momentarily thereafter, a pairof tuckers 68 move from the positions of FIG. into the web contactingpositions of FIGS. 4 and 14 to re-shape the web from the FIG. 13 intothe FIG. 14 configuration.

As best shown in FIG. 11, tuckers 68 include a pivotally mounted arm thefree end of which carries an inwardly opening U-shaped channel member74, flared as a guide at its upstream end 76 and vertically taperingdownstream from the transverse configuration of FIG. 14 to thevertically reduced configuration shown at the downstream end 78.Movement of the web through tuckers 68 thus effects progressive marginalfold-over of the web as best shown in FIG. 15. Both shoe 63 and tuckers68 remain in the pleat forming FIG. 11 position until withdrawn toretracted positions momentarily prior to the arrival of a trailing pad,such retraction being necessary to prevent interference with the spacedpads. As best shown in FIGS. 11, 15, and 16, side marginal areas of rampportions 62 and 64 are reduced in thickness in respect to the centralportion thereof. Those ramp areas provide support for marginal areas ofthe web during pleat forming. Such reduction permits the tab centerplies and top pleat to move through the channels .of tuckers 68 abovethe ramp with the bottom pleat moving therethrough beneath the ramp withthe tucker channels tapered to the desired extent which is difficultwith thicker ramp margins. After substantially simultaneous passage ofthe pleated web beyond the elevated ramp shelf 64 and through thetuckers 68, that pleat previously below the ramp moves upwardly. towardits adjacent tab end underply to be ironed into symmetry with the upperpleat as below described.

' Upon leaving the trailing ends 78 of tucker channel members 74, themarginally folded web passes in the configuration shown in FIG. 15between a pair of heated ironing rolls 71 and 73, as closely spaceddownstream as the structure permits. Rolls 71 and 73 are fixedly mountedon journalled shafts 79 and 81, respectively, those shafts being drivenin counter-rotation by-mechanical connection to a main drive shaft 92,as indicated by the dotted lines 91. Rolls 71 and 73' are provided withflats and 77. The flats relieve minor portions of the roll diameter, forexample about 160 thereof, to allow passage, as the flats move intoregistry, of the web enclosed pads therebetween at the end of theironing stage.

Structural details of the mechanism which operates the constricting shoe63, tuckers 68 and the ironing rolls 71 and 73 in the manner shown inFIGS. 4 and 5 are shown in FIGS. 6 toll inclusive. As best shown inFIGS. 6 to 8, constricting shoe 63 is attached to a pivot arm 98 fixedto extend radially from one end of a rock shaft 100 journalled in abearing assembly 102 to extend transversely of the'pat-h of web travel,assembly 102 being supported by framework 40. The opposite end of shaft100 carries a cam follower arm 104 provided with a roller 106 with arm104 biased-by spring 108 into engaging contact with a cam plate 110mounted on the main drive shaft 92 to synchronize actuation of theconstricting shoe with actuation of the tucker mechanism.

Tuckers 68 and extension members 82 are fixed to pivotally mounted arms80 which are reciprocally cam driven between the dotted and full linepositions shown in FIG. 6 by a pair of cup cams 88. As shown in FIG. 9,cams 88 are fixed to and drivenby shaft 92, journalled at 90. Camfollowers 86 affixed;to arms 80, are maintained engaged with earns 88 bya retraction spring 89 extending under tension between the arms.

. As best shown in FIG. 10, arms 80 are mounted to pivot about bearings84 mounted in a supporting assembl 85. Cup cams 88 are spaced on thedrive shaft 92 to permit conveyor pulley 54 to be rotatably mountedtherebe-' between shoe 63 and tuckers 68 is obtained both by properdesign of the cam contour and by its circumferentially fixed position onshaft 92 in respect to cams 88. That position may, if desired, beadjusted by a suitable shaft locking device, not shown. As abovementioned, a drive connection illustrated by phantom lines 91 causesironing rolls 71 and 73 to be driven by shaft 92 in synchronism with thereciprocation of tuckers 68 through cup cams 88 and with the actuatingof constricting shoe 63. The linear speed of the conveyor 44 is suitablysynchronized with the rotational speed of drive shaft 92 in a knownmanner from the common source of power, such connection not being shown.

To prevent the web from being burned between the hot rolls 71 and 73following shut-down of the machine, constriction shoe 63 isautomatically raised by a known protective circuit associated with aretracting piston unit 112 and the hot rolls 71 and 73 aresimultaneously spaced apart by a similar unit 114. The circuit rendersunits 112 and 114 operable during machine stoppage and inoperable duringoperation thereof.

As is evident from the above description of the method and apparatus,the width of the resulting over-folded pleats may be varied by alteringthe width of both the ramp portion 62 and portion 70' of the nip-formingshoe 63 in respect to the perimeter of the tubular web, the extent oflongitudinal web overlap not being a controlling factor. Sanitarynapkins currently produced by applicants assignee and sold under thetrademark Kotex are of a pad size defining a web perimeter duringfabrication of about 6%". Factors inherent in the bellows typeinpleating method such as the required displacement of the web whilesubstantially tensioned and the resulting stresses limit tab ends formedfrom a similar tube to a width of about 1%". However, with the presentover-pleating method, the pleats may, as above mentioned, be formedwider than shown in FIGS. 1 and 2. For example, pleats may be formed ofsulficient width to bring the inner margins of the pleats substantiallyinto abutment. The provision of such pleats reduces the width of the tabends formed from a tubular web of 6% perimeter to about 1%. Theresulting narrowed tab ends are more easily looped through belts,

hence may be preferred by some users.

Referring particularly to FIG. 3, it is evident that proper pinning ofthe tab ends shown results in a pin strength greater than is obtained bypinning a tab end having either C-folded pleats or a tab end providedmarginally with pleats of inwardly directed V configura tion. Thefastening pin normally pierces only four web thicknessesin the area ofeach pleated margin, whether C-folded or inpleated in outwardly open Vconfiguration, while piercing six web thicknesses in the area of eachtab end margin pleated in the manner herein taught.

It is thus seen that the invention offers a very wide degree offlexibility in respect to the formation of outwardly closed over-foldedand symmetrically paired marginal tab end pleats. Sanitary napkins maybe so pleated with relative ease at high production speed and offer manyadvantages during use.

We claim:

1. The method of symmetrically double pleating the margins of sanitarynapkin tab ends comprising the steps of forming an elongate continuouslymoving assembly of wrapper enclosed spaced pads while maintaining thewrapper tensioned between the pads, momentarily shaping wrapper portionsbetween successive pads substantially into I-beam configurationtransversely across the width of the assembly, folding inwardly wrapperportions forming the ends of the I-beam configuration into symmetricallydisposed U-configurations which are inwardly open and outwardly closed,and thereafter pressing said folded back portions into contactingengagement with contiguous marginal portions of the tab ends whereby themarginal edges of said tab ends are provided with six thicknesses ofwrapper material.

2. The improved method of pleating the tab ends of absorbent bandages inwhich an assembly of like elongate pads in end to end spaced relationare enclosed within a continuously moving enclosing wrapper whilesubjecting the wrapper to suflicient tension to maintain between thepads a tubular configuration of substantially the transverse perimeterof the enclosed pads, said improvement comprising intermittentlysubjecting a central portion of the width of said tubular wrappermaterial between successive pads to suflicient transverse constrictionsubstantially' to narrow the configuration of said central portion inrespect to outer non-constricted portions, shaping and inwardly foldingthe outer non-constricted wrapper portions in a manner to form a pair ofsymmetrical inwardly extending marginal pleats with one pleat of eachpair disposed on each side of the constricted portion of the wrapper toprovide the edges of the wrapper in the area between pads with sixthicknesses of material, and thereafter subjecting the marginally foldedwrapper to heat and pressure to iron the portions thus pleated intosubstantially planiform configuration.

3. The method of claim 2 wherein the shaping of the non-constrictedmarginal portions of the wrapper is effected by causing those wrapperportions continuously to pass through marginal tuckers of progressivelynarrowing configuration.

4. The method of making sanitary napkins comprising enclosing aplurality of absorbent pads within an elongated wrapper of liquidpervious foldable material, tensioning the wrapper sufficiently tomaintain those portions between the pads in substantially thecross-sectional configuration of the pads, moving the wrapper andenclosed pads at uniform speed along the longitudinal axis of the pluralpad assembly, subjecting a central portion of said wrapper during itsmovement past a station fixed in respect to the path of movement to aconstricting nip extending transversely of the direction of Wrappertravel and of lesser width than that of the pads, momentarily toestablish a generally I-beam configuration transversely of the Wrapper,and thereafter folding inwardly portions of the material forming eachend of the -I-beam configuration toward the centrally constrictedwrapper portion to obtain a symmetrically disposed pair ofU-configurations which are inwardly open and outwardly closed to providethe edges .of the wrapper portion between pads with six thicknesses ofmaterial, and thereafter feeding the folded wrapper between heatedpressure rolls to iron the symmetrically disposed portions against thecentral wrapper portion.

5. Apparatus of the character described having in combination, means forforming a continuously moving assembly of spaced pads enclosed in anelongate wrapper, means maintaining the wrapper sufiiciently tensionedto insure a tubular configuration between the pads of substantially thetransverse perimeter of the pads, means for intermittently shaping thetransverse wrapper perimeter between successive pads into an I-beamconfiguration, means closely spaced downstream from said first means forre-forming end portions of said I-beam configuration into symmetricallydisposed U-configurations, and means downstream from the last mentionedmeans for flattening the wrapper from said symmetrically disposedU-configurations into a multi-ply tab end with the said symmetricallydisposed portions flattened into integral overpleats extendingmarginally along each face of the tab end thus formed.

6. In apparatus (for the pleating of pad wrapper tab ends, thecombination with means for continuously enclosing a plurality of spacedpads within an elongate foldable wrapper, means for moving the padenclosing wrapper at a constant speed while maintained bridged intubular configuration between the pads, means for intermittently forminga nip extending transversely of and of less width than the transversewrapper dimension for passage therethrough of a central portion of thetubular wrapper to re-form the transverse configuration thereof in thearea between pads into a generally I-beam shape, intermittently operablemeans spaced adjacent said nip in the direction of wrapper travel forthe progressively increased over-folding of the material forming endportions of the 'I-beam configuration, and means for thereafter pressingthe wrapper material into fiat tab ends between pads with theover-folded wrapper portions flattened into symmetrical pleats onopposite sides of and extending along the margins of the tab end.

7. Apparatus of the character described comprising means forcontinuously moving a plurality of spaced pads, means for encirclingsaid pads with a continuously moving Wrapper material, means maintainingthe wrapper tensioned to bridge consecutive pads in tubularconfiguration, means intermittently operative in the time interval ofmovement of successively spaced and wrapper pads thereby verticallyconstricting the central area of the pad bridging wrapper portionsbetween pads along a path disposed transversely of and narrower than thepath of wrapper travel, means for shaping the non-constricted portionsof the tubular wrapper between pads into progressively narrowinginwardly directed substantially U configurations, and means for ironingthe configuration thus formed into multiple ply tab ends with the Uportions of the wrapper material flattened to form symmetrical pleats onopposite sides of marginal areas of a tab end thus formed.

8. Apparatus for the manufacture of sanitary napkins from a web offoldable wrapper material continuously fed thereto and a succession ofabsorbent pads fed in spaced relation onto said web, means forsuccessive over- -folding of marginal portions of the Web to form a tubeenclosing the pads and bridging the spaces therebetween, meanslongitudinally tensioning the wrapper to maintain the pad bridgingportions in tubular configuration, means movable t and from the path ofwrapper travel and positioned downstream from the tube forming means andadapted intermittently to re-shape the tubular wrapper between pads intosubstantially a transverse I-beam configuration, second re-shaping meansdownstream of the first re-shaping means and movable to and from thepath of wrapper travel for changing said transverse I-beam configurationinto symmetrically disposed U-configurations which are inwardly open andoutwardly closed, and means downstream from said second re-shaping meansfor flattening the inwardly disposed portions of said U-configurationsagainst adjacent web portions to provide a pair of symmetric marginalover-pleats.

9. The apparatus of claim 8 wherein the means forming the I-beam wrapperconfiguration comprises a member fixed in and'extcnding transversely ofthe path of wrapper travel for the support of the lower central portionof the wrapper tube, a constricting shoe of substantially the transversewidth of said fixed member mounted for movement between a retractedposition above to a position within the path of pad travel, said shoewhen in the latter position being spaced above said fixed member at adistance to constrict a central portion of the tube momentarily toestablish said transverse I-beam configuration.

10. The apparatus of claim 8 wherein the re-shaping means forming thesymmetrically disposed U-configurations comprises a pair of marginaltuckers mounted and synchronously connected for movement from retractedpositions laterally of the path of tube travel to a position ofengagement with those portions of the formed wrapper tube immediatelyupstream thereof into the ends of the I-beam configuration, said tuckersbeing of someing in a downstream direction with the sides thereofopentuckers serve a funnel-like function to over-fold portions of theweb forming the ends of the I-beam configuration to effect symmetricallydisposed U-configurations which are inwardly open and outwardly closed.

11. The apparatus of claim 9 including means for the actuation of bothsaid first and second re-shaping means in timed relation to the spacedpositions of the web drawn pads, means for actuating said constrictingshoe from a retracted to a nip forming position momentarily afterpassage of a pad past the path of shoe travel and for retracting saidshoe momentarily prior to movement of a trailing pad into that path.

12. The apparatus of claim 10 including means timed in respect to thespacing of said pads for the actuation of said tuckers from retracted toweb engaging positions momentarily following passage of a pad throughthe paths of movement thereof and retraction from said Web engagingpositions momentarily prior to the passage of a trailing pad throughsaid paths of movement.

13. In apparatus of the type described, a conveyor driven at uniformspeed and having a downstream end defined by a support pulley, meansfeeding a continuous web material to said conveyor, means feedinguniformly spaced pads onto the web, means folding the web in tubularconfiguration over the pads, means maintaining the Web tensioned toretain tubular configuration of the pad bridging web portions, a ramp inclose proximity to said pulley and extending upwardly of the conveyorpath, a portion of the ramp being narrower than the width of the padsand positioned symmetrically of their path of travel, means downstreamof the conveyor for drawing the web and enclosed pads over the ramp withthe web maintained tensioned, a web-constricting member mounted formovement from a position above the path of pad movement over the ramp toa position above the ramp within the path of pad movement, said memberextending transversely of the pad path in substantial registry with saidnarrow ramp portion and spaced, when in said path, sufliciently abovethe ramp to form a constricting nip therebetween for transversere-shaping of the web perimeter in the area between pads into agenerally I-beam configuration, means intermittently operable frompositions laterally of the path of pad travel to positions of engagementwith the outer non-restricted web portions progressively to re-shape theweb perimeter into symmetrically disposed U-configurations which areinwardly open and outwardly closed, and means timing the actuation ofsaid nip-forming member and said subsequent re-shaping means in respectto the rate at which the spaced pads travel over the ramp.

References Cited by the Examiner DONALD W. PARKER, Primary Examiner.

HAROLD B. WHITMORE, Examiner.

C. F. ROSENBAUM, Assistant Examiner.

1. THE METHOD OF SYMMETRICALLY DOUBLE PLEATING THE MARGINS OF SANITARYNAPKIN TAB ENDS COMPRISING THE STEPS OF FORMING AN ELONGATE CONTINUOUSLYMOVING ASSEMBLY OF WRAPPER ENCLOSED SPACED PADS WHILE MAINTAINING THEWRAPPER TENSIONED BETWEEN THE PADS, MOMENTARILY SHAPING WRAPPER PORTIONSBETWEEN SUCCESSIVE PADS SUBSTANTIALLY INTO I-BEAM CONFIGURATIONTRANSVERSELY ACROSS THE WIDTH OF THE ASSEMBLY, FOLDING INWARDLY WRAPPERPORTIONS FORMING THE ENDS OF THE I-BEAM CONFIGURATION INTO SYMMETRICALLY